|
0
|
1 /*
|
|
|
2 * Copyright (C) 2007, 2009 Free Software Foundation, Inc.
|
|
|
3 *
|
|
|
4 * This file is free software; you can redistribute it and/or modify it
|
|
|
5 * under the terms of the GNU General Public License as published by the
|
|
|
6 * Free Software Foundation; either version 3, or (at your option) any
|
|
|
7 * later version.
|
|
|
8 *
|
|
|
9 * This file is distributed in the hope that it will be useful, but
|
|
|
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
|
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
|
12 * General Public License for more details.
|
|
|
13 *
|
|
|
14 * Under Section 7 of GPL version 3, you are granted additional
|
|
|
15 * permissions described in the GCC Runtime Library Exception, version
|
|
|
16 * 3.1, as published by the Free Software Foundation.
|
|
|
17 *
|
|
|
18 * You should have received a copy of the GNU General Public License and
|
|
|
19 * a copy of the GCC Runtime Library Exception along with this program;
|
|
|
20 * see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
|
|
|
21 * <http://www.gnu.org/licenses/>.
|
|
|
22 */
|
|
|
23
|
|
|
24 #if __PREC == 32
|
|
|
25 #define X87CW (0 << 8) /* Single precision (24 bits) */
|
|
|
26 #elif __PREC == 64
|
|
|
27 #define X87CW (2 << 8) /* Double precision (53 bits) */
|
|
|
28 #elif __PREC == 80
|
|
|
29 #define X87CW (3 << 8) /* Extended precision (64 bits) */
|
|
|
30 #else
|
|
|
31 #error "Wrong precision requested."
|
|
|
32 #endif
|
|
|
33
|
|
|
34 #define X87CW_PCMASK (3 << 8)
|
|
|
35
|
|
|
36 static void __attribute__((constructor))
|
|
|
37 set_precision (void)
|
|
|
38 {
|
|
|
39 unsigned short int cwd;
|
|
|
40
|
|
|
41 asm volatile ("fstcw\t%0" : "=m" (cwd));
|
|
|
42
|
|
|
43 cwd &= ~X87CW_PCMASK;
|
|
|
44 cwd |= X87CW;
|
|
|
45
|
|
|
46 asm volatile ("fldcw\t%0" : : "m" (cwd));
|
|
|
47 }
|
